UI Patterns showcase theme based on the Bootstrap Drupal 8 theme.
Run:
$ composer install
Thanks to the integration with Drupal Component Scaffold
you'll find a fully functional Drupal 8 site under ./build.
After that proceed with the site installation and setup:
$ cd build
$ drush si standard -y --db-url=mysql://username:password@host/database
$ drush en ui_patterns_library -y
$ drush then bootstrap_patterns -y
$ drush config-set system.theme default bootstrap_patterns -y
$ drush cr
Then visit the Patterns Overview page at /patterns.